Kolbe Windows & Doors has partnered with LuxWall, Inc. to bring vacuum insulating glass (VIG) to residential design. LuxWall’s VIG technologies--called Enthermal™ and Enthermal Plus™--will be available as glass options in select Kolbe® products in the near future.
But what exactly is VIG? How does it work? What does it offer to a window or door design?
Below are answers to a few frequently asked questions about VIG and the future of this technology at Kolbe.
The most familiar item in your home or office that would compare to VIG is an insulated coffee mug. In VIG, a small, virtually airless space is created between two panes of glass. This is called a vacuum. The vacuum dramatically limits the amount of thermal energy that can pass through the glass.
VIG is used in conjunction with a low-emissivity (low-E) coating that reflects heat from solar radiation. Compared to traditional insulating glass (IG), VIG also keeps the center of glass (COG) temperature warmer, limiting thermal energy loss from convection. The vacuum space itself is the most novel feature, removing all substances--including air--from between the glass, limiting thermal energy loss from conduction.
So, just as an insulated coffee mug keeps hot beverages warm, when an interior space is heated, less warmth will be lost through VIG. And just as an insulated coffee mug keeps chilled beverages cool, when the sun beats down on VIG from the exterior, the air-conditioned interior will remain cooler longer. VIG helps maintain both types of climate-controlled spaces!
LuxWall represents this essential VIG system with Enthermal. Enthermal Plus includes the VIG and a third lite with an additional low-E coating, allowing for customization options, modified performance, and alternative sizing.
LuxWall’s VIG products--Enthermal and Enthermal Plus--represent another path for windows and doors to meet heightened energy requirements and create truly comfortable environments. When incorporated into Kolbe windows and doors, VIG helps a variety of built environments use their energy efficiently, improve occupant experiences, and more.
Simulations of Enthermal and Enthermal Plus in Kolbe product confirm significantly better performance than the best dual-pane argon-filled IG units. When considering the total U-value--which helps identify how well a building material insulates--VIG has provided an improvement greater than 0.06. This makes it a suitable alternative to triple pane IG.
A sample of simulated performance values for select Kolbe products is shown below. Lower U-values represent more effective insulation.
VIG directly addresses the energy use--and waste--of buildings. Buildings are responsible for consuming 30 percent of the world’s energy. In turn, 39 percent of global carbon dioxide greenhouse gas emissions is produced by buildings.
When analyzing where buildings experience energy loss, windows are one of the primary elements to consider. Windows often allow too much thermal energy to escape or enter a building, reducing the efficacy of climate controls. Addressing this disadvantage through innovation is critical.
While VIG compares to triple pane glass in some ways, technologies like Enthermal also offer design and customization options that triple pane does not. Because VIG only requires two panes with a small gap, it could fit into standard sashes or historical single pane frames. The fewer materials required in its manufacturing also represent lower embodied carbon.
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Yes. Enthermal and Enthermal Plus are specifically manufactured as fully tempered glass products. Further, Enthermal can be implemented into window and door products using standardized and time-tested glazing techniques.
LuxWall is a manufacturer based out of Ypsilanti, Michigan. This organization was formed with a clear focus on creating reliably effective and aesthetically pleasing vacuum insulating glass in the United States. Experts in the fields of glass manufacturing, materials science, applied physics, and process engineering work on Enthermal with funding from several significant energy-conscious investors, including the United States Department of Energy.
There will be some key restrictions to keep in mind.
Enthermal and Enthermal Plus will be available in sizes as small as 12 by 18 inches up to 60 by 96 inches. These dimensions are reversible. Only rectangular VIG will be available upon launch, meaning it will not be an option for radius windows or other geometric shapes. Only rectangular performance divided lite patterns will be available. Rectangular grilles in the airspace will be available for Enthermal Plus.
Enthermal Plus will only be available with the VIG positioned to the exterior of the opening. Requests for custom glass options to integrate into Enthermal Plus will be reviewed on a case-by-case basis.
Both Enthermal and Enthermal Plus will feature a 20-year warranty.
Enthermal features a vacuum port. This is a small, covered hole about the size of a pencil eraser. It is situated in a single, upper corner of the glazing depending on the proportions and orientation of the glass. See the diagrams below for details. The hole cannot be repositioned or removed; however, a small, discreet, black metal cover will conceal it.
To maintain the airless gap, Enthermal also uses what are called “pillars.” These small, stainless-steel structures are positioned throughout the glass to hold the two panes of glass apart, and they are visible in the glazing from certain angles. LuxWall allows some variance in the positioning of these pillars.
Visible between the panes at one point along the edge of Enthermal is also a small rectangular tool called a “getter.” The getter helps capture any substances that may remain between the glass as the vacuum is created.
Visit our Where to Buy page to connect with your local Kolbe partner and express your interest! As the official launch approaches and more resources are made available, our partners will work with you to answer any additional questions you may have.
LuxWall’s Enthermal and Enthermal Plus are estimated to be available in select Kolbe products starting August 29th, 2025. Stay tuned for additional information before and after launch to help you make the best choice for your Kolbe window or door integrated with VIG.
Thank you for your interest in VIG and Enthermal. Kolbe and LuxWall look forward to seeing this innovative glass solution incorporated into your design visions soon.